Simulation of visible light communications in vehicular networks

The rapid development in the field of lighting and illumination allows low energy consumption and a rapid growth in the use, and development of solid-state sources. As the efficiency of these devices increases and their cost decreases there are predictions that they will become the dominant source for general illumination in the short term. The objective of this thesis is to study, through extensive simulations in realistic scenarios, the feasibility and exploitation of visible light communication (VLC) for vehicular ad hoc networks (VANETs) applications. A brief introduction will introduce the new scenario of smart cities in which visible light communication will become a fundamental enabling technology for the future communication systems. Specifically, this thesis focus on the acquisition of several, frequent, and small data packets from vehicles, exploited as sensors of the environment. The use of vehicles as sensors is a new paradigm to enable an efficient environment monitoring and an improved traffic management. In most cases, the sensed information must be collected at a remote control centre and one of the most challenging aspects is the uplink acquisition of data from vehicles. My thesis discusses the opportunity to take advantage of short range vehicle-to-vehicle (V2V) and vehicle-to-roadside (V2R) communications to offload the cellular networks. More specifically, it discusses the system design and assesses the obtainable cellular resource saving, by considering the impact of the percentage of vehicles equipped with short range communication devices, of the number of deployed road side units, and of the adopted routing protocol. When short range communications are concerned, WAVE/IEEE 802.11p is considered as standard for VANETs. Its use together with VLC will be considered in urban vehicular scenarios to let vehicles communicate without involving the cellular network. The study is conducted by simulation, considering both a simulation platform (SHINE, simulation platform for heterogeneous interworking networks) developed within the Wireless communication Laboratory (Wilab) of the University of Bologna and CNR, and network simulator (NS3). trying to realistically represent all the wireless network communication aspects. Specifically, simulation of vehicular system was performed and introduced in ns-3, creating a new module for the simulator. This module will help to study VLC applications in VANETs. Final observations would enhance and encourage potential research in the area and optimize performance of VLC systems applications in the future.

Poor performance of microbiological sampling in the prediction of recurrent arthroplasty infection

During a two-stage revision for prosthetic joint infections (PJI), joint aspirations, open tissue sampling and serum inflammatory markers are performed before re-implantation to exclude ongoing silent infection. We investigated the performance of these diagnostic procedures on the risk of recurrence of PJI among asymptomatic patients undergoing a two-stage revision. A total of 62 PJI were found in 58 patients. All patients had intra-operative surgical exploration during re-implantation, and 48 of them had intra-operative microbiological swabs. Additionally, 18 joint aspirations and one open biopsy were performed before second-stage reimplantation. Recurrence or persistence of PJI occurred in 12 cases with a mean delay of 218 days after re-implantation, but only four pre- or intraoperative invasive joint samples had grown a pathogen in cultures. In at least seven recurrent PJIs (58%), patients had a normal C-reactive protein (CRP, < 10 mg/l) level before re-implantation. The sensitivity, specificity, positive predictive and negative predictive values of pre-operative invasive joint aspiration and CRP for the prediction of PJI recurrence was 0.58, 0.88, 0.5, 0.84 and 0.17, 0.81, 0.13, 0.86, respectively. As a conclusion, pre-operative joint aspiration, intraoperative bacterial sampling, surgical exploration and serum inflammatory markers are poor predictors of PJI recurrence. The onset of reinfection usually occurs far later than reimplantation.

Adaptive behavioural syndromes due to strategic niche specialization

BACKGROUND: Behavioural syndromes, i.e. consistent individual differences in behaviours that are correlated across different functional contexts, are a challenge to evolutionary reasoning because individuals should adapt their behaviour to the requirements of each situation. Behavioural syndromes are often interpreted as a result of constraints resulting in limited plasticity and inflexible behaviour. Alternatively, they may be adaptive if correlated ecological or social challenges functionally integrate apparently independent behaviours. To test the latter hypothesis we repeatedly tested helpers in the cooperative breeder Neolamprologus pulcher for exploration and two types of helping behaviour. In case of adaptive behavioural syndromes we predicted a positive relationship between exploration and aggressive helping (territory defence) and a negative relationship between these behaviours and non-aggressive helping (territory maintenance). RESULTS: As expected, helpers engaging more in territory defence were consistently more explorative and engaged less in territory maintenance, the latter only when dominant breeders were present. Contrary to our prediction, there was no negative relationship between exploration and territory maintenance. CONCLUSION: Our results suggest that the three behaviours we measured are part of behavioural syndromes. These may be adaptive, in that they reflect strategic specialization of helpers into one of two different life history strategies, namely (a) to stay and help in the home territory in order to inherit the breeding position or (b) to disperse early in order to breed independently.

The Other Side of the Doors: Butte & Beyond -- Congressman Pat Williams “In the Crucible of Change”

Pat Williams emerged from the Mining City of Butte, Montana with a sense of grassroots, people-oriented politics. His inherent belief in the power of ordinary citizens carried him through the Montana Legislature and into Congress for a record-setting period. The accomplishments of his long career partially obscured his innate progressive and populist instinct that is reflective of the period of “in the Crucible of Change.” This film addresses Pat’s early years when his progressive instincts and activities resulted in pushback from the giant Anaconda Company which had held Montana hostage for 75 years. Pat is joined for part of the film by former campaign staffer, and now prominent media consultant, Michael Fenenbock for reflections on Pat’s 1978 “Door-to-Door to Congress” campaign, which demonstrated the power of his belief in the people on the other side of the doors. Pat Williams (b. 1937) rose from teaching grade school in his hometown of Butte, MT, to serving for the longest number of consecutive terms (9 terms, 18 years) in the US House of Representatives of anyone in Montana history. Pat was a member of the National Guard and attended UM in Missoula and William Jewel College, graduating from the University of Denver. Pat also served in the Montana legislature for 2 terms (1966 & 1968 elections). In 1969. Pat helped his legislative seat-mate John Melcher get elected as Montana’s Eastern District Congressman in the Special Election that June. Pat went to Washington DC as Melcher’s Executive Assistant. Upon returning to Montana, Pat headed up the Montana offices of the innovative Mountain Plains Family Education Program. In 1974, Pat ran unsuccessfully for Montana’s Western District Congressional seat in a three-way race with former Congressman Arnold Olsen and state Legislator Max Baucus. After the drafting and passage of the 1972 Montana Constitution, Pat was named a member of Montana’s first-ever Reapportionment Commission. In 1978 he successfully ran for Congress, conducting a massive grass-roots door-to-door campaign of 1½ years, reaching 50,000 doors. In a hotly contested 6-way Democratic primary, Pat won going away and also handily won the general election. Pat served in Congress from January, 1979 until January of 1997, 14 years representing the Western District and 4 years representing the entire state. Upon his retirement from Congress, in 1997 Williams returned to Montana where has been an instructor at the University of Montana and Senior Fellow and Regional Policy Associate at the Center for the Rocky Mountain West. He is a former member of the Montana Board of Regents and serves on a number of national education-related boards. In Congress Pat was a Deputy Whip of the U.S. House of Representatives and sat on committees on: Budget, Natural Resources, Education and Labor, and Agriculture. Pat’s leadership helped pass trailblazing legislation to assist hard-working middle-class families and ensure opportunities for every child. Pat’s fingerprints are on many pieces of important legislation, including the College Middle Income Assistance Act, the Family and Medical Leave Act, the Toddlers and Childhood Disability Act, the Library Services and Construction Act, and the Museum Services Act. Pat successfully sponsored the Lee Metcalf Wilderness Area and the Rattlesnake Wilderness area, helped save the Bob Marshall Wilderness from oil and gas exploration, and helped ban geothermal energy drilling near the borders of Yellowstone National Park. As Chairman of The Post-Secondary Education Committee, he protected the National Endowment for the Arts from elimination, a remarkable undertaking during a very trying time for the Agency. Pat worked tirelessly with Tribal College Leaders to build Montana’s seven Tribal Colleges. He was also responsible for the legislation that created The American Conservation Corps, which became the Corporation for National Service, giving thousands of America’s young people a chance to serve their country and pursue higher education. Pat lives in Missoula with his wife Carol Griffith Williams, former Montana Senate Majority Leader. They have three children and five grandchildren.

Archiving Montana’s Geologic Data

Since the 19th century, enormous amounts of time and money were invested in the exploration and development of Montana’s natural resources. These investments generated tremendous volumes of geologic, geophysical, and environmental data. Over the years, many of these data have been stored, forgotten, lost, or destroyed. In this lecture, Peggy discusses the steps the Bureau is taking to rescue and make the data available to the public.

Libre Courseware For Bayesian Decision Making

This paper describes the ideas and problems of the Edukalibre e-learning project, in which the author takes part. The basic objective of the project shares the development and exploitation of software components for web-based information systems applied to education as well as organizing of teaching material for them. The paper concerns a problem of the mathematical-oriented courseware and describes the experience in developing LaTeX-supporting online converting tool.

Relation of vocational identity statuses to interest structure among Swiss adolescents

Vocational identity is one core component of identity construction in adolescence. The current study investigated whether vocational interest structure in terms of differentiation, coherence, elevation, and interest-aspiration congruence would differentiate among students in vocational identity achievement, foreclosure, moratorium, and diffusion. Swiss students at the beginning of eighth grade (N = 341) participated in the study. Groups were created using cluster analysis based on the dimensions of career exploration and career commitment, and group differences were explored with discriminant analysis. Controlling for sociodemographic variables, higher interest differentiation and elevation distinguished students in achievement/moratorium from those in diffusion. More interest elevation differentiated moratorium from foreclosure. (Contains 1 figure and 3 tables.)

Increasing the career choice readiness of young adolescents: an evaluation study

A career workshop that applies models of the Cognitive Information Processing Approach (Sampson, Reardon, Peterson, & Lenz, 2004) and incorporates critical ingredients (Brown and Ryan Krane, 2000) to promote the career choice readiness of young adolescents was developed and evaluated with 334 Swiss students in seventh grade applying a Solomon four group design with a three-month follow-up. Participants significantly increased their performance in terms of career decidedness, career planning, career exploration, and vocational identity. Implications for evaluation research and counselling practice are presented.

Adaptable Visualisation Based On User Needs

Software developers often ask questions about software systems and software ecosystems that entail exploration and navigation, such as who uses this component?, and where is this feature implemented?. Software visualisation can be a great aid to understanding and exploring the answers to such questions, but visualisations require expertise to implement effectively, and they do not always scale well to large systems. We propose to automatically generate software visualisations based on software models derived from open source software corpora and from an analysis of the properties of typical developers queries and commonly used visualisations. The key challenges we see are (1) understanding how to match queries to suitable visualisations, and (2) scaling visualisations effectively to very large software systems and corpora. In the paper we motivate the idea of automatic software visualisation, we enumerate the challenges and our proposals to address them, and we describe some very initial results in our attempts to develop scalable visualisations of open source software corpora.

Anreizformen und Ausschöpfungsquoten bei postalischen Befragungen. Eine Prüfung der Reziprozitätshypothese

Mittels eines Methodenexperiments mit zwei randomisierten Versuchsgruppen (N jeweils 200) und einer Kontrollgruppe (N=200) wird untersucht, ob und in welchem Ausmaß Geschenke bei einer postalischen Befragung zur Erhöhung der Ausschöpfungsquote beitragen. Es zeigt sich, dass ein versprochenes Geschenk (Telefonkarte im Wert von 10 Schweizer Franken) die Ausschöpfungsquote nicht erhöht, während ein dem Fragebogen beigelegtes Geschenk zu einem Anstieg der Quote um zirka 10 Prozentpunkte führt. Die Befunde stehen in Einklang mit der Reziprozitätshypothese, derzufolge Vorleistungen von vielen Personen auch dann honoriert werden, wenn die reziproke Handlung nicht dem unmittelbaren Eigeninteresse eines Akteurs entspricht.

Chemical Composition of Micrometer-Sized Filaments in an Aragonite Host by a Miniature Laser Ablation/Ionization Mass Spectrometer

Detection of extraterrestrial life is an ongoing goal in space exploration, and there is a need for advanced instruments and methods for the detection of signatures of life based on chemical and isotopic composition. Here, we present the first investigation of chemical composition of putative microfossils in natural samples using a miniature laser ablation/ionization time-of-flight mass spectrometer (LMS). The studies were conducted with high lateral (similar to 15 mu m) and vertical (similar to 20-200 nm) resolution. The primary aim of the study was to investigate the instrument performance on micrometer-sized samples both in terms of isotope abundance and element composition. The following objectives had to be achieved: (1) Consider the detection and calculation of single stable isotope ratios in natural rock samples with techniques compatible with their employment of space instrumentation for biomarker detection in future planetary missions. (2) Achieve a highly accurate chemical compositional map of rock samples with embedded structures at the micrometer scale in which the rock matrix is easily distinguished from the micrometer structures. Our results indicate that chemical mapping of strongly heterogeneous rock samples can be obtained with a high accuracy, whereas the requirements for isotope ratios need to be improved to reach sufficiently large signal-to-noise ratio (SNR). Key Words: Biogenicity-Biomarkers-Biosignatures-Filaments-Fossilization. Astrobiology 15, 669-682.

Highlighting the Importance of Researching Family Homelessness

This invited commentary responds to and builds upon Tobin and Murphy's article, “Addressing the Challenges of Child and Family Homelessness.” In affirming the ideas emerging from this article, Hallett and Tierney provide three points of extension: (1) more research needs to be conducted with doubled-up families; (2) the role of shame needs further exploration; and, (3) additional work needs to be done to increase access to postsecondary institutions.

Cocolos, emigración y narrativa dominicana

El desarrollo de la industria azucarera en la República Dominicana requirió mano de obra para el corte de caña y el trabajo en el ingenio. La dificultad en atraer trabajadores locales resultó en la contratación de obreros de las islas inglesas Anguila, St. Kitts, Antigua, Nevis, Tórtola, etc., donde el masivo desempleo provocado por la industrialización facilitaba el traslado de los isleños hacia las zafras dominicanas. En San Pedro de Macorís, lugar de su asentamiento, se los llamaba despectivamente “cocolos". Esta ponencia intenta estudiar la historia y delineación de estos obreros inmigrantes, su conducta, su idiosincrasia y modo de vida en el ingenio desde la narrativa dominicana del siglo XX. Las obras seleccionadas son un espejo del racismo, del rechazo cultural y de la explotación de los cocolos en el cañaveral. Cabe destacar que las novelas recientes asumen tardíamente una actitud reivindicatoria ante la ausencia de estudios críticos al respecto.

En el espejo del Bicentenario

Se analizan condiciones históricas de la conformación de la Región del Noroeste argentino, con sus particulares características, así como incidencias del proceso revolucionario de 1810 y algunas repercusiones del mismo en el futuro de la Región. Se acude para ello al aporte de estudios históricos, lingüísticos y antropológicos regionales, así como al testimonio de pensadores comprometidos con su realidad. La población descendiente de los pueblos originarios aparece sumergida en situaciones de desigualdad y explotación a lo largo del período recorrido, lo que se expresa a través de obras de luchadores como M. A. Tanco, J. L. Torres y el grupo Tarja. En la actualidad, y a pesar de los avances realizados a nivel de Acuerdos y Declaraciones de organismos internacionales, la demanda de su legítimo y efectivo reconocimiento es una deuda pendiente, lo que conlleva connotaciones éticas que cuestionan las bases de nuestro sistema democrático.

Política y comunicación : el impacto de la Ley de Servicios de Comunicación Audiovisual en el escenario mediático

El año 2009 significó para Argentina un momento de discusiones que provocaron interpelaciones al sistema democrático. Después 26 años de recuperada la democracia, el Estado modificó la dictatorial legislación que regula los servicios de comunicación audiovisuales. Esto implica una ampliación de la democratización del sistema de medios, tanto en las voces presentes, como en los autorizados para su uso y explotación. Esta nueva legislación permite que más y diversos sujetos puedan hacer uso de su derecho a comunicar y obliga a los oligopolios de la comunicación a ceder parte de sus licencias, de ahí las presiones económicas para frenar la nueva norma.